Many agricultural practices produce significant environmental problems. Years of row crop production dependent upon intensive cultivation of the soil has led to considerable soil erosion and with it, nutrient loss from fields into America’s lakes, rivers, and then the oceans into which rivers flow. Vital nutrients often travel with the soil, creating additional problems including the hypoxic zone in the Gulf of Mexico. Meanwhile, back in farm fields, the use of monoculture cropping techniques, highly dependent on chemicals to protect against competing weeds and insects, have led to growing water quality, biodiversity, and human safety issues. All the while this common system of intensive tillage and reliance on fossil-fuel based fertilizers contributes to wildlife degradation and greenhouse gas emissions.

Many agriculture programs established through the federal farm bill offer solutions to farmers through technical advice, cost sharing, and land payments to reduce the environmental impacts of agriculture. In many ways, these programs provide the only backstop to complete degradation of numerous ecosystems, wildlife habitats, and watersheds. Moreover, these programs offers some of the most cost-effective solutions available while providing vital environmental protection and employment opportunities in rural America.

Learn more about some of the major environmental issues on agricultural lands today, and how USDA Farm Bill Conservation Programs are helping to address those problems:

Erosion and Nutrient Runoff

Over 100 million agricultural acres across the U.S. currently experience unsustainable soil erosion rates, making soil erosion the leading pollution problem for U.S. rivers and streams. Soil lost from farm fields enters water as suspended particles.

Why Are Suspended Particles Harmful?

Soil particles shade out lower depths of water...

preventing plant growth

limiting fish growth and populations

Particles accumulate through the process of sedimentation. These accumulating sediments can:

impede the ability of sight-feeding fish to find food

clog fishes' gills, blocking their oxygen absorption

bury and suffocate eggs and larvae

All of these impacts cause reduce growth and populations, increase illness and shifts in aquatic community composition. The accumulation of millions of tons of soil annually disrupts not only water habitat for wildlife, but also barge traffic channels, requiring costly and destructive dredging. Sedimentation also creates costs for the thousands of communities that obtain drinking water from rivers. In total, erosion from conventional agriculture practices costs tax payers and consumers an estimated $8 billion to $13 billion per year.

Fertilizer

Nitrogen fertilizer is often added to soils under traditional cropping methods to support corn-intensive rotations. In conventional agricultural systems, nitrogen is added in a single, large dose often not synchronized to plant demand which requires a low, steady supply of nitrogen. Since plants cannot immediately use the applied nitrogen and the soil under intensive tillage loses much of its nitrogen holding capacity, much of the applied nitrogen is lost to the atmosphere or to the water supply. Soil erosion is a major cause of nutrient runoff; roughly 90% of all nitrogen and phosphorus received into water bodies result from erosion.

The impacts of nutrients in waterways continue to persist for months after entering the water supply and continue literally thousands of miles away. Agricultural nutrients, nitrogen and phosphorus in particular, from the corn and soybean-intensive region of southern Minnesota, Iowa, Illinois, Indiana and Ohio have been found to contribute to the hypoxic zone, or "dead zone" in the Gulf of Mexico

Manure

Manure from large concentrations of agricultural animals also cause environmental stress. Manure not only carries considerable nitrates and contributes to nitrate pollution problems, it also carries numerous pathogens including E-coli, Salmonella, and Cryptosporidium -- all of which can survive in manure outside of an animal’s body for extended periods.

Rural drinking wells may become contaminated when manure is applied on lands with shallow water tables. Improper handling can allow manure to enter surface water, threatening not only human health with the spread of pathogens, but the health and survival of fish and wildlife as well.

How Conservation Programs Can Address Erosion and Nutrient Runoff

Farm Bill programs designed to assist and encourage farmers and land owners to implement erosion prevention practices can have a significant positive impact in reducing erosion and nutrient loss from farmlands.

The Conservation Reserve Program (CRP) provides a rental payment to farmers to take their land out of production and plant perennial grasses. Establishing a year-round cover and ending repetitive tilling reduces erosion from agricultural lands by up to 95 percent while at the same time providing valuable wildlife habitat vital for the survival of a number of species.

The Conservation Stewardship Program (CSP) pays farmers already implementing conservation practices on their working land while providing them an incentive to implement more conservation practices.

The Environmental Quality Incentives Program (EQIP) provides cost-share assistance to farmers to help them implement techniques such as riparian buffers, grasses waterways, and treed windbreaks that catch soil and nutrients before they can enter waterways. Additionally, EQIP can provide cost share assistance to livestock farmers to install anaerobic digesters which capture and eliminate methane emissions from stored livestock waste while reducing the nutrient runoff potential of the manure when applied to fields.

Agricultural Chemicals

Pesticides, herbicides, and other chemical treatments designed to reduce competition for crops from insects and weeds often also have fates similar to nitrogen and other applied nutrients, leaching into ground water or running off into surface waters, creating health hazards for humans and the environment.

In a study by the United States Geologic Survey, pesticides were found in 97% of streams tested in agricultural areas. The most frequently detected herbicides in surface waters included atrazine, acentanilides, and 2,4-D, all commonly used in agriculture. Pesticides, even at low levels, have been shown to affect fish and amphibian species, often sending shockwaves through the entire food chain and ecosystem. Moreover, 61% of all shallow groundwater sources in agricultural areas tested positive for pesticides. Once ground-water contamination occurs, it is difficult to reverse.

The considerable pesticide and chemical presence in America’s waters creates considerable health impacts and costs to Americans. Atrazine, present in 97 percent of waterways in agricultural areas, reduces the blood's ability to carry oxygen. Atrazine and other agricultural chemicals have been linked to causing birth defects, various cancers, and other health issues. In total, agricultural chemicals result in billions of dollars of health care costs each year.

Many agricultural chemicals are designed to reduce the competition row crops face from weeds and insects. Farmers spend billions of dollars each year on such inputs in hopes of realizing a larger yield and profit at harvest. However, a number of techniques are available that reduce weed and insect competition while eliminating chemical runoff and increasing farmers profit margins.

Cover crops and organic agricultural practices use natural plants to out-compete pests or to provide natural methods to control insects via natural competitors. EQIP provides funding to assist farmers in implementing cover crops or to transition their farm to organic production. The Conservation Reserve Program (CRP) and Grassland Reserve Program (GRP) both offer assistance and funding to farmers to plant perennial grasses that can better compete against weeds and insects without the aid of chemicals.

Irrigation Degrading Land and Destroying Water Supply

Throughout many arid regions of the United States, irrigation has served to provide stable and timely water supply to crops; helping farmers to consistently produce bumper crops.

Years of irrigation, however, have led to two chronic problems:

Salinization of irrigated lands and over-drawn water tables -- Continued irrigation of land from ground water sources brings with it minerals, including small amounts of salt. Unlike water which percolates through the subsoil or runs off the surface, salts build up over time where they are deposited, eventually making the land unfarmable.

Water tables are not recharged at a pace that matches the consumption from irrigation systems -- Each year, ground water levels beneath 14 million acres of irrigated crop land fall between 6 inches and 5 feet.

Conventional agricultural production has often challenged biodiversity. In the years following settlement of the North American continent, many species of native wildlife benefited slightly from the small introduction of agriculture by settlers by causing an increase in diversification of food and cover on landscapes still dominated by native plant communities. However, as agriculture expanded and increased in its ability to alter the landscape, most native wildlife species declined; reducing biodiversity. Conversion of native diverse plant communities to monoculture agricultural plantings continues to stand as the greatest challenge to biodiversity and wildlife habitat.

AWEP and EQIP Can Reduce the Need for Irrigation

Farmers often implement irrigation systems to avoid temporary drought conditions which periodically occur. However, there are other methods farmers may use to address water issues without relying on costly infrastructure that can, over time, degrade soils and destroy groundwater supplies.

Conservation tillage reduces or eliminates tillage practices. Crops are planted into the residue of the previous crop, skipping multiple tillage steps that remove crop residue and break up the soil into small, loose pieces. This practice has been found to help soils retain more water near the root zone for subsequent crops; dramatically reducing and sometimes eliminating the need for irrigation. Farmers can obtain assistance through EQIP to transition to a conservation tillage system.

The Agricultural Water Enhancement Program (AWEP) helps farmers update irrigation systems to more water-efficient technologies, reducing the amount of water farmers draw from ground water supplies while also slowing the process of salinization that occurs with heavy irrigation.

Agriculture’s Impact on Wildlife

Since settlement time, North America has lost over 85 percent of its forest, wetland, and grassland acres to agricultural land conversion. This loss of millions of acres is compounded by suburban sprawl as well as the breaking up of larger natural ecosystems by agricultural production areas. By segmenting these ecosystems and using :

The wildlife carrying capacity of the remaining habitat is greatly diminished.

Deteriorating water quality dramatically alters lower-level organisms that form the foundation of the food chain.

Atrazine, an herbicide, has been found to mutate amphibians and disrupt their reproductive organs.

Pesticides kill both target and not target insects, destroying the food supplies of many bird species and bats, effectively destabilizing entire food chains and ecosystems.

Numerous Farm Bill Programs Help Preserve Habitat Values

Federal programs play significant roles in assisting farmers and landowners to implement techniques to protect wildlife. Land management programs designed to reduce erosion or produce other nutrient management benefits also produce benefits to wildlife.

In addition, the Wetlands Reserve Program (WRP) offers long-term or permanent easements to landowners as well as cost-share funding to restore vital habitat to its original condition. WRP protects 1.9 million acres of valuable wetlands. Without such support, these wetlands face the real threat of conversion to farmland.

Impact of Industrial Agriculture on Climate Change

Industrial agricultural practices have a heavy reliance on fossil fuel inputs, with production focused on maximizing yield rather than efficiency. This reliance results in considerable greenhouse gas emissions. Nitrogen fertilizer is often applied to cropland in one single, large dose, which plants cannot easily or quickly use. If not taken up in a short period by plants, that nitrogen is either lost to rain which carries it to waterways, or nitrogen becomes volatized, turning into a gas and escaping to the atmosphere where it contributes to climate change. Per molecule, nitrous oxide has 310 times the heat trapping ability compared to carbon dioxide. And agriculture contributes 74 percent of all domestic nitrous oxide emissions.

In addition, agriculture is a major source of methane gas, which has 22 times the heat trapping ability of carbon dioxide. Methane develops as a result of breakdown of organic or plant material by bacteria. Cows and other rumens have such bacteria in their stomachs, resulting in some direct methane emissions. More importantly, when animal waste is stored in a liquid form without oxygen, considerable amounts of methane are released. Agriculture produces 28 percent of all domestic methane emissions.

Finally, the common practice of intensive land cultivation often results in extended periods of soil exposed to the air. This lack of land cover, which persists for up to five months out of the year for many agricultural fields, results in considerable carbon emissions. Plants that sequestered carbon from the atmosphere during the growing season become carbon emitters when tilled into the soil to make way for the next year’s crop. Agriculture loses an estimated 19 million metric tons of carbon dioxide to the atmosphere each year due to often unnecessary intensive cultivation practices.